This invention relates generally to one way motion transmission systems and apparatus and, more particularly, to a one way motion transmission system and apparatus for connecting one or more rotatable input devices, such as one or more chain driven sprocket wheel members, to a rotatable output device such as the rear wheel of a bicycle.
At the present time, there are basically four commercially available one way motion clutch transmission systems including (1) spring loaded ball or roller on ramp type systems, (2) sprag type systems, (3) ratchet type systems, and (4) Torrington type systems. These presently available systems are relatively heavyweight and/or expensive and/or noisy and/or slow acting, and/or limited in load bearing capacity.
The present invention provides a relatively lightweight, low cost, quiet operating and fast acting one-way motion transmission system having high load or torque bearing capacity. While the illustrative embodiments of the invention are herein disclosed in connection with a bicycle drive system, the inventive concepts are applicable to other types of bicycle drive systems and to other drive systems in which the presently available one-way motion systems are commonly used.
The present invention may be usefully employed with conventional bicycle drive systems wherein a chain member is driven by a pedal operated front sprocket wheel and drives one or more rear sprocket wheels operatively connected to the rear wheel of the bicycle.
The present invention is also applicable to a dual drive system of the type comprising a pair of reciprocable drive members, such as chain or cable members, which are drivably connected to the pedals of a bicycle and alternately driven during the alternate power input portions of the pedal movement. Each of the drive members are alternately drivably connected and drivably disconnected relative to the rear wheel to continuously drive the rear wheel in a forward direction while the pedals are being driven by a rider while also being disconnected whenever pedal movement terminates to provide a free wheeling condition for the rear wheel. A bicycle drive system of this type is described in my U.S. Pat. No. 4,133,550 for BICYCLE AND POWER TRANSMISSION SYSTEM, the disclosure of which is incorporated herein by reference.
The inventive concepts are also widely applicable to other kinds of drive systems, other than bicycle drive systems, wherein rotary input motion is utilized to provide one-way rotary output motion.
In general, the inventive concepts may be summarized as comprising a rotary force input means, such as a chain driven sprocket wheel; a rotary force output means, such as a bicycle wheel, to be driven only in one (forward) desired direction by the input means; rotatable force transmission means including at least one transmission element movable between a first force transfer position, directly positively connecting the rotary motion input means to the rotary force output means through the transmission means only upon application of force to the rotary force input means in a direction to cause the one desired direction of movement of the output means, and a second non-force transfer position disconnecting the rotary force input means from the rotary force output means upon termination of the application of force to the rotary force input means in a direction to cause the one direction of movement of the rotary force output means; and transmission actuating means operably associated with the one element of the transmission means for causing movement thereof to the first force transfer position in response to the application of force to the rotary force input means in the direction causing the one direction of movement of the rotary force output means and for causing movement thereof to the second non-force transfer position upon termination of application of force to the rotary force input means in the one desired direction of movement of the rotary force output means, the actuating means being arranged and constructed to have substantially no force transfer nor load bearing relationship with the input means, the output means, or the transmission means in the first force transfer position nor in the second non-force transfer position.